I am using an Intel 5100 card with a AVM 7141 WiFi router set on WPA2. Even though I have configured the connection in the NetworkManager, it does not connect. It does in fact not do anything when I click on the connection in the menu. However, configuring the network in wpa-roam.conf, then stopping the Network-Manager via [/etc/init.d/network-manager stop] and executing [ifdown wlan0 && ifup wlan0] gets me connected. As soon as I start the network manager via [/etc/init.d/network-manager start], the connection is lost. (earlier today it sufficed to just disable WiFi in the NetworkManager context menu, but not anymore)

Does anybody know what could cause this? I would really appreciate having all my networking in one place.